1. Field of the Invention
The present invention relates generally to electrophotographic and other document printing devices, and more particularly to a print line comprising devices usable upstream and/or devices usable downstream from an electrophotographic or other printing or document reproduction apparatus for performing various pre-processing operations on a recording medium input into the printing apparatus and/or post-processing operations on the documents output from the printing apparatus.
2. Description of the Related Art
Electrophotographic printing and reproduction devices are well known. Typically, a photoconductive member is charged to a uniform potential and thereafter exposed to a light image of an original document to be reproduced. The exposure discharges the photoconductive member in areas corresponding to the background of the document being reproduced and creates a latent image on the photoconductive member. Alternatively, in a laser-beam printer or the like, a light beam is modulated and used to selectively discharge portions of the photoconductive member in accordance with image information. With either type of apparatus, the latent image on the photoconductive member is visualized by developing the image with a developer powder commonly referred to as “toner.” Most systems employ developer which comprises both charged carrier particles and charged toner particles which triboelectrically adhere to the carrier particles. During development of the latent image, the toner particles are attracted from the carrier particles by the charged pattern of image areas on the surface of the photoconductive member to form a visualized toner image on the photoconductive member. This toner image is then transferred to a recording medium such as paper or the like for viewing by an end user. Typically, the toner is fixed to the surface of the paper through the application of heat and pressure.
Following the successful reproduction of one or more documents in this fashion, it is often desirable to perform pre-processing functions on the recording medium and/or one or more of a wide variety of post-processing functions on the printed documents. For example, the recording medium required by a continuous feed printing apparatus may be a band/roll of paper. Upstream of the continuous feed printer a respective pre-processor such as an unwinder or the like is necessary to feed the paper from the band/roll into the continuous feed printer. The continuous feed printer prints an image or the like on the paper and a respective post-processor such as a rewinder is necessary downstream the continuous feed printer to rewind the band/roll. Other post-processors like burster/trimmer/stacker, cutter, inserter, post-printers, label stickers or the like may also be applied. For example, certain applications require the selective addition of color or other enhancements to the printed documents using ink jet annotation or the like, application of magnetic ink character recognition media, job/document serial number and account auditing, insertion of pages into the printed documents, brail embossing, perforation, slitting, envelope stuffing, and postage metering.
In the prior art, a print product capable of performing a requested print processing is formed by combining plural modules, i.e. dedicated physically modular pre- and/or post-processing devices and a printing apparatus, in a single standalone printing product. Such a physically modular product is not easily reconfigured and the constituting components can typically not be used on other products without extensive revision of the control software.
U.S. Pat. No. 5,559,606, assigned to the same assignee as the present invention, describes a standalone printing product comprising a controller and a plurality of modules, which may be of different vendors, in an arbitrary configuration. Each of the modules includes an associated processor storing data related to operational constraints of the associated modules and a bus interconnects the processors to the controller for directing the operation of the modules. The controller is adapted to operate independent of a particular configuration of the plurality of modules by receiving from each of the processors the data related to the operational constraints of each associated module and interrogating each of the processors to determine the geometrical relationship of the interconnection of the modules. The controller then responds to the data related to the operational constraints of each of the processors and to the geometrical relationship of the interconnection of the modules to dynamically configure the image processing apparatus to operate in accordance with the operational constraints of each of the processors and to the geometrical relationship of the interconnection of the modules.
Once such a standalone printing product comprising plural modules has been defined, creating print engines in accordance with said printing product, for instane for a particular customer need, is significiantly simplified. In the ideal case, one simply selects which modules and how many of each are required, and ships them to the customer to be assembled on site.
In a printshop environment, plural pre- and post-processing devices and appropriate printing apparatuses and/or standalone printing products are combined to constitute a print line for performing a specific print processing dependent on the printshop requirements. The pre- and post-processing functions can be carried out off-line with one or more dedicated pre- and/or post-processing devices. Of course, the modules are specially designed to perform certain specific pre- or post-processing functions, so that a specific print line is only adapted to perform a specific print processing. The performance of other required print processing necessitates the replacement of some or all of these modules in their entirety.
Accordingly, a need has been recognized for a re-configurable print line allowing for an easy and efficient configuring of thereof with respect to a requested print processing without inducing substantial hardware or software modifications. The subject invention is deemed to meet the foregoing needs and others, and to provide a method of processing data in a printing system comprising a plurality of printing and print-related devices, wherein data is transmitted over a common print line bus, the printing devices and print-related devices being connected to the common print line bus by means of associated print line bus adapters to constitute a printshop environment, the method enabling for easily configuring and re-configuring the plurality of printing and print-related devices in accordance with a requested print processing.